.TH POCKETSPHINX 1 "2022-09-27"
.SH NAME
pocketsphinx \- Run speech recognition on audio data
.SH SYNOPSIS
.B pocketsphinx
[ \fIoptions\fR... ]
[ \fBlive\fR |
\fBsingle\fR |
\fBhelp\fR |
\fBsoxflags\fR ]
\fIINPUTS\fR...
.SH DESCRIPTION
.PP
The ‘\f[CR]pocketsphinx\fP’ command-line program reads single-channel
16-bit PCM audio one or more input files (or ‘\f[CR]-\fP’ to read from
standard input), and attemps to recognize speech in it using the
default acoustic and language model. The input files can be raw audio,
WAV, or NIST Sphere files, though some of these may not be recognized
properly.  It accepts a large number of options which you probably
don't care about, and a \fIcommand\fP which defaults to
‘\f[CR]live\fP’. The commands are as follows:
.TP
.B help
Print a long list of those options you don't care about.
.TP
.B config
Dump configuration as JSON to standard output (can be loaded with the
‘\f[CR]-config\fP’ option). 
.TP
.B live
Detect speech segments in input files, run recognition on them (using
those options you don't care about), and write the results to standard
output in line-delimited JSON. I realize this isn't the prettiest
format, but it sure beats XML. Each line contains a JSON object with
these fields, which have short names to make the lines more readable:
.IP
"b": Start time in seconds, from the beginning of the stream
.IP
"d": Duration in seconds
.IP
"p": Estimated probability of the recognition result, i.e. a number between
0 and 1 which may be used as a confidence score
.IP
"t": Full text of recognition result
.IP
"w": List of segments (usually words), each of which in turn contains the
‘\f[CR]b\fP’, ‘\f[CR]d\fP’, ‘\f[CR]p\fP’, and ‘\f[CR]t\fP’ fields, for
start, end, probability, and the text of the word. In the future we
may also support hierarchical results in which case ‘\f[CR]w\fP’ could
be present.
.TP
.B single
Recognize the input as a single utterance, and write a JSON object in the same format described above.
.TP
.B align

Align a single input file (or ‘\f[CR]-\fP’ for standard input) to a word
sequence, and write a JSON object in the same format described above.
The first positional argument is the input, and all subsequent ones
are concatenated to make the text, to avoid surprises if you forget to
quote it.  You are responsible for normalizing the text to remove
punctuation, uppercase, centipedes, etc. For example:

.EX
    pocketsphinx align goforward.wav "go forward ten meters"
.EE

By default, only word-level alignment is done.  To get phone
alignments, pass `-phone_align yes` in the flags, e.g.:

.EX    
    pocketsphinx -phone_align yes align audio.wav $text
.EE        

This will make not particularly readable output, but you can use
.B jq
(https://stedolan.github.io/jq/) to clean it up.  For example,
you can get just the word names and start times like this:

.EX    
    pocketsphinx align audio.wav $text | jq '.w[]|[.t,.b]'
.EE        

Or you could get the phone names and durations like this:

.EX    
    pocketsphinx -phone_align yes align audio.wav $text | jq '.w[]|.w[]|[.t,.d]'
.EE        

There are many, many other possibilities, of course.
.TP
.B help
Print a usage and help text with a list of possible arguments.
.TP
.B soxflags
Return arguments to ‘\f[CR]sox\fP’ which will create the appropriate
input format. Note that because the ‘\f[CR]sox\fP’ command-line is
slightly quirky these must always come \fIafter\fP the filename or
‘\f[CR]-d\fP’ (which tells ‘\f[CR]sox\fP’ to read from the
microphone). You can run live recognition like this:

.EX
    sox -d $(pocketsphinx soxflags) | pocketsphinx -
.EE

or decode from a file named "audio.mp3" like this:

.EX
    sox audio.mp3 $(pocketsphinx soxflags) | pocketsphinx -
.EE
.PP
By default only errors are printed to standard error, but if you want more information you can pass ‘\f[CR]-loglevel INFO\fP’. Partial results are not printed, maybe they will be in the future, but don't hold your breath. Force-alignment is likely to be supported soon, however.
.SH OPTIONS
.TP
.B \-agc
Automatic gain control for c0 ('max', 'emax', 'noise', or 'none')
.TP
.B \-agcthresh
Initial threshold for automatic gain control
.TP
.B \-allphone
phoneme decoding with phonetic lm (given here)
.TP
.B \-allphone_ci
Perform phoneme decoding with phonetic lm and context-independent units only
.TP
.B \-alpha
Preemphasis parameter
.TP
.B \-ascale
Inverse of acoustic model scale for confidence score calculation
.TP
.B \-aw
Inverse weight applied to acoustic scores.
.TP
.B \-backtrace
Print results and backtraces to log.
.TP
.B \-beam
Beam width applied to every frame in Viterbi search (smaller values mean wider beam)
.TP
.B \-bestpath
Run bestpath (Dijkstra) search over word lattice (3rd pass)
.TP
.B \-bestpathlw
Language model probability weight for bestpath search
.TP
.B \-ceplen
Number of components in the input feature vector
.TP
.B \-cmn
Cepstral mean normalization scheme ('live', 'batch', or 'none')
.TP
.B \-cmninit
Initial values (comma-separated) for cepstral mean when 'live' is used
.TP
.B \-compallsen
Compute all senone scores in every frame (can be faster when there are many senones)
.TP
.B \-dict
pronunciation dictionary (lexicon) input file
.TP
.B \-dictcase
Dictionary is case sensitive (NOTE: case insensitivity applies to ASCII characters only)
.TP
.B \-dither
Add 1/2-bit noise
.TP
.B \-doublebw
Use double bandwidth filters (same center freq)
.TP
.B \-ds
Frame GMM computation downsampling ratio
.TP
.B \-fdict
word pronunciation dictionary input file
.TP
.B \-feat
Feature stream type, depends on the acoustic model
.TP
.B \-featparams
containing feature extraction parameters.
.TP
.B \-fillprob
Filler word transition probability
.TP
.B \-frate
Frame rate
.TP
.B \-fsg
format finite state grammar file
.TP
.B \-fsgusealtpron
Add alternate pronunciations to FSG
.TP
.B \-fsgusefiller
Insert filler words at each state.
.TP
.B \-fwdflat
Run forward flat-lexicon search over word lattice (2nd pass)
.TP
.B \-fwdflatbeam
Beam width applied to every frame in second-pass flat search
.TP
.B \-fwdflatefwid
Minimum number of end frames for a word to be searched in fwdflat search
.TP
.B \-fwdflatlw
Language model probability weight for flat lexicon (2nd pass) decoding
.TP
.B \-fwdflatsfwin
Window of frames in lattice to search for successor words in fwdflat search 
.TP
.B \-fwdflatwbeam
Beam width applied to word exits in second-pass flat search
.TP
.B \-fwdtree
Run forward lexicon-tree search (1st pass)
.TP
.B \-hmm
containing acoustic model files.
.TP
.B \-input_endian
Endianness of input data, big or little, ignored if NIST or MS Wav
.TP
.B \-jsgf
grammar file
.TP
.B \-keyphrase
to spot
.TP
.B \-kws
file with keyphrases to spot, one per line
.TP
.B \-kws_delay
Delay to wait for best detection score
.TP
.B \-kws_plp
Phone loop probability for keyphrase spotting
.TP
.B \-kws_threshold
Threshold for p(hyp)/p(alternatives) ratio
.TP
.B \-latsize
Initial backpointer table size
.TP
.B \-lda
containing transformation matrix to be applied to features (single-stream features only)
.TP
.B \-ldadim
Dimensionality of output of feature transformation (0 to use entire matrix)
.TP
.B \-lifter
Length of sin-curve for liftering, or 0 for no liftering.
.TP
.B \-lm
trigram language model input file
.TP
.B \-lmctl
a set of language model
.TP
.B \-lmname
language model in \fB\-lmctl\fR to use by default
.TP
.B \-logbase
Base in which all log-likelihoods calculated
.TP
.B \-logfn
to write log messages in
.TP
.B \-loglevel
Minimum level of log messages (DEBUG, INFO, WARN, ERROR)
.TP
.B \-logspec
Write out logspectral files instead of cepstra
.TP
.B \-lowerf
Lower edge of filters
.TP
.B \-lpbeam
Beam width applied to last phone in words
.TP
.B \-lponlybeam
Beam width applied to last phone in single-phone words
.TP
.B \-lw
Language model probability weight
.TP
.B \-maxhmmpf
Maximum number of active HMMs to maintain at each frame (or \fB\-1\fR for no pruning)
.TP
.B \-maxwpf
Maximum number of distinct word exits at each frame (or \fB\-1\fR for no pruning)
.TP
.B \-mdef
definition input file
.TP
.B \-mean
gaussian means input file
.TP
.B \-mfclogdir
to log feature files to
.TP
.B \-min_endfr
Nodes ignored in lattice construction if they persist for fewer than N frames
.TP
.B \-mixw
mixture weights input file (uncompressed)
.TP
.B \-mixwfloor
Senone mixture weights floor (applied to data from \fB\-mixw\fR file)
.TP
.B \-mllr
transformation to apply to means and variances
.TP
.B \-mmap
Use memory-mapped I/O (if possible) for model files
.TP
.B \-ncep
Number of cep coefficients
.TP
.B \-nfft
Size of FFT, or 0 to set automatically (recommended)
.TP
.B \-nfilt
Number of filter banks
.TP
.B \-nwpen
New word transition penalty
.TP
.B \-pbeam
Beam width applied to phone transitions
.TP
.B \-pip
Phone insertion penalty
.TP
.B \-pl_beam
Beam width applied to phone loop search for lookahead
.TP
.B \-pl_pbeam
Beam width applied to phone loop transitions for lookahead
.TP
.B \-pl_pip
Phone insertion penalty for phone loop
.TP
.B \-pl_weight
Weight for phoneme lookahead penalties
.TP
.B \-pl_window
Phoneme lookahead window size, in frames
.TP
.B \-rawlogdir
to log raw audio files to
.TP
.B \-remove_dc
Remove DC offset from each frame
.TP
.B \-remove_noise
Remove noise using spectral subtraction
.TP
.B \-round_filters
Round mel filter frequencies to DFT points
.TP
.B \-samprate
Sampling rate
.TP
.B \-seed
Seed for random number generator; if less than zero, pick our own
.TP
.B \-sendump
dump (compressed mixture weights) input file
.TP
.B \-senlogdir
to log senone score files to
.TP
.B \-senmgau
to codebook mapping input file (usually not needed)
.TP
.B \-silprob
Silence word transition probability
.TP
.B \-smoothspec
Write out cepstral-smoothed logspectral files
.TP
.B \-svspec
specification (e.g., 24,0-11/25,12-23/26-38 or 0-12/13-25/26-38)
.TP
.B \-tmat
state transition matrix input file
.TP
.B \-tmatfloor
HMM state transition probability floor (applied to \fB\-tmat\fR file)
.TP
.B \-topn
Maximum number of top Gaussians to use in scoring.
.TP
.B \-topn_beam
Beam width used to determine top-N Gaussians (or a list, per-feature)
.TP
.B \-toprule
rule for JSGF (first public rule is default)
.TP
.B \-transform
Which type of transform to use to calculate cepstra (legacy, dct, or htk)
.TP
.B \-unit_area
Normalize mel filters to unit area
.TP
.B \-upperf
Upper edge of filters
.TP
.B \-uw
Unigram weight
.TP
.B \-var
gaussian variances input file
.TP
.B \-varfloor
Mixture gaussian variance floor (applied to data from \fB\-var\fR file)
.TP
.B \-varnorm
Variance normalize each utterance (only if CMN == current)
.TP
.B \-verbose
Show input filenames
.TP
.B \-warp_params
defining the warping function
.TP
.B \-warp_type
Warping function type (or shape)
.TP
.B \-wbeam
Beam width applied to word exits
.TP
.B \-wip
Word insertion penalty
.TP
.B \-wlen
Hamming window length
.SH AUTHOR
Written by numerous people at CMU from 1994 onwards.  This manual page
by David Huggins-Daines <dhdaines@gmail.com>
.SH COPYRIGHT
Copyright \(co 1994-2016 Carnegie Mellon University.  See the file
\fILICENSE\fR included with this package for more information.
.br
.SH "SEE ALSO"
.BR pocketsphinx_batch (1),
.BR sphinx_fe (1).
.br
